Tammy Abraham scored a stoppage-time equaliser to complete an incredible comeback and rescue a point for Chelsea at West Bromwich Albion after they had trailed 3-0 at half-time.

A mistake by Marcos Alonso led to the hosts’ first, Matheus Pereira feeding Callum Robinson to produce a classy finish past Willy Caballero, who was starting in place of dropped £71m keeper Kepa Arrizabalaga.

Thiago Silva, who was making his Premier League debut for Chelsea, was then too casual in possession, allowing Robinson to pounce and run at goal before doubling the lead with another impressive finish.

Remarkably, it was quickly 3-0 as Kyle Bartley was left unmarked to tap home inside the six-yard box after the visitors failed to deal with a corner.

But Frank Lampard’s side rallied after the break and Mason Mount reduced the deficit from 20 yards.

Substitute Callum Hudson-Odoi set up a tense finale with a stylish finish, before Abraham, making his first top-flight start of the season, tapped home the equaliser in the 93rd minute after Mount’s shot had been saved.

Although West Brom boss Slaven Bilic was unhappy the goal stood because of a Havertz handball in the build-up.

He said: “It’s not maybe handball – it is handball. It’s so obvious I don’t even want to talk about it.”

Mixed feelings for Lampard

Blues boss Frank Lampard looked furious slumped in his seat in the dugout after sending his players out early for the start of the second half following a horrific defensive display.

Having been handed the captain’s armband on his first Premier League appearance since arriving on a free transfer, this was supposed to be a day to remember for 36-year-old Brazil centre-back Silva.

Instead, his mistake allowed Robinson to get his second after the former Sheffield United forward had broken the deadlock following Alonso’s careless header.

It went from bad to worse when no-one picked up defender Bartley to make it 3-0, before Chelsea finally got a grip thanks to goals from three homegrown players.

Since the start of last season, Chelsea have conceded more away Premier League goals than any other team but as bad as they were at the back, Lampard’s side were always a threat going forward.

Timo Werner had already hit the bar when Baggies keeper Sam Johnstone was left rooted to his line by Mount’s finish, which launched the comeback.

Hudson-Odoi’s classy finish left West Brom a bag of nerves, although it took until the third minute of stoppage time for Abraham to equalise.

Despite spending £200m-plus on strengthening his squad, Lampard still has work to do if Chelsea are to claim another top-four finish.

Having lost against champions Liverpool last weekend, they have dropped five points in their past two games and looked a mess during a shambolic first 45 minutes.

Baggies let it slip

This was a case of so near yet so far for West Brom, who are still searching for a first win since returning to the Premier League.

They have conceded 11 goals in 270 minutes of top-flight action – but when the dust settles Slaven Bilic will surely seize on the positives from this incident-packed encounter.

Robinson showed excellent composure for both his finishes, while Pereira has been directly involved in three of West Brom’s five Premier League goals this season.

After following up his goal and assist at Everton last week, the Brazilian provided the pass for Robinson’s first goal.

Abraham’s late equaliser will hurt but if Bilic can tighten up his defence, the Baggies could give themselves a fighting chance this season after showing they have the ammunition to cause problems in attack.

‘We knew second half would be hard’ – what they said

West Brom boss Slaven Bilic: “We played the game we wanted to play. You can’t plan you are going to outclass them but you can outrun them, have the right determination and concentration, make them make mistakes and punish them.

“We knew the second half was going to be hard for us. We knew we would have to defend as a team quite deep and the plan was to limit them to shots outside the box.

“It’s disappointing as the boys did well enough to get all three points.”

One of the best Premier League comebacks? The stats

• Chelsea are the first Premier League team since West Ham in February 2011 to avoid defeat after trailing by three or more goals at half-time, a game which was also against West Brom at The Hawthorns and also ended 3-3.
• West Brom are the first English top-flight side to concede 11 goals in their opening three league games since Arsenal in 1963-64 (12).
• Chelsea have failed to keep a clean sheet in 20 of their 21 Premier League away games under Lampard.
• Robinson’s four goal involvements in the Premier League have all come against ‘big six’ sides, scoring three times against Chelsea and providing an assist versus Manchester United.
• Chelsea were 3-0 down after 27 minutes against West Brom – only against Manchester City in February 2019 (19 minutes) have they been three goals down earlier in a Premier League match.
• Silva is the first outfield player to make an error leading to a goal on their Premier League debut since Issa Diop for West Ham against Arsenal in August 2018.

What’s next?

While West Brom have a week to prepare for a league game at Southampton on 4 October (12:00 BST), Chelsea are away to Tottenham in the fourth round of the Carabao Cup on Tuesday (19:45).